Acinetobacter baumannii (Ab) is an emerging pathogen that causes primary and opportunistic infections, and is a serious concern in the hospital and battlefield setting. This organism has significant intrinsic resistance to antibioticsas well as an ability to quickly acquire new resistance. Additionally, Ab can persist in a desiccated state on fomites, making disinfection and management of nosocomial infections particularly troublesome. The goal of this research proposal is to find unexploited therapeutic approaches by elucidating the role of uncharacterized genes of Ab in this organism's mechanisms of pathogenesis, resistance, and persistence. Three projects will be established to 1) use a genomic approach to broadly identify the role of uncharacterized genes (Colin Manoil, Project 1 Director) 2) determine the role of envelope integrity with regard to bacterial viability (Sam Mille, PI/PD, Project 2 Director), and use expression analysis to identify genes and sRNAs of unknown function associated with drug, disinfectant, and desiccation tolerance (Carrie Harwood, Project 3 Director). The work of the Center will be supported by an Administrative Core (Core 1, John Kemner Core Leader), a Protein Interaction Technology Core (Jim Bruce Core 2 Director Leader), and a Data Dissemination/Resource Management Core (Mitch Brittnacher, Core 3 Director).